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|1. (WO2013118559) FOCUS ADJUSTMENT DEVICE, CAMERA SYSTEM AND FOCUS ADJUSTMENT METHOD|
|Applicants:||OLYMPUS IMAGING CORP.
|Title:||FOCUS ADJUSTMENT DEVICE, CAMERA SYSTEM AND FOCUS ADJUSTMENT METHOD|
The purpose of the invention is to improve the ability to track a moving body during continuous shooting and thereby allow for high-speed and accurate focus adjustment. A control unit of a camera body performs initial position driving for moving a focus lens with the driving amount and the driving direction for the initial position driving set to Li, on the basis of the magnitude of the speed of an object (the slope of an object movement profile (H)) detected by an object speed detection unit, so as to satisfy the relationship Lh < (Ls - Lps + Li), where Lh is the amount of image plane movement by the object, Ls is the scan driving range, Lps is the scan driving range required for detecting a peak, and Li is the initial position driving amount. Thereby, the object movement profile (H) and the scan driving amount profile (S) of a focus lens intersect in an interval (k4) where contrast autofocus is implemented. Thereafter, the control unit performs a scan driving operation in the interval (k4) and reliably detects a focus point regardless of the magnitude of the image plane moving speed of an object (the slope of the object movement profile (H)).